Police prosecutor Jess King showed three CCTV videos to the court showing the assault on May 16 on the then-52-year-old manager Mark Hurst.

About 8.45pm, Stannard ordered a drink at the bar and tried to pay using a debit card, which was declined multiple times.

The footage showed Mr Hurst standing at the cash register when Stannard leaned over the bar and snatched the debit card from his hand before walking off.

Next, Mr Hurst followed Stannard through the bistro area to pursue payment.

Seconds after Mr Hurst approached him, Stannard tackle-like assaulted him using one arm, pulling him along and then tumbling onto the floor, Mr Hurst hitting his head on furniture.

Mr Hurst sustained a cut to his head and concussion.

The incident was witnessed by children and other customers in the bistro area.

Ms King said patrons had to pull Stannard off. He left the bistro but was apprehended outside by an off-duty police officer.

Defence lawyer Lachlan Ygoa-McKeown said Stannard had a bad day at work and had been drinking at the bar since knock-off.

He said his client had not been drinking for some time prior to this day.

"He had developed a habit of drinking until... he fell asleep or was unconscious,” Mr Ygoa-McKeown said.

He said this developed as a result of growing up in a violent household until his mother left his father, taking him and his younger sister with her and living on the streets for a year, before his father murdered his mother.

The court heard this was not the first time Stannard was convicted for assault.

Stannard offered, through his lawyer, a letter of apology to Mr Hurst and $1000 in compensation.

Magistrate Jeff Clarke urged Stannard to continue his rehabilitation.

He was fined $500, ordered to pay $1000 compensation and complete 40 hours of community service for his "unacceptable behaviour” in front of children.